improvement(vscode): Recommend some extensions

.vscode/extensions.json

@@ -0,0 +1,16 @@
+{
+	// See https://go.microsoft.com/fwlink/?LinkId=827846 to learn about workspace recommendations.
+	// Extension identifier format: ${publisher}.${name}. Example: vscode.csharp
+
+	// List of extensions which should be recommended for users of this workspace.
+	"recommendations": [
+		"ms-vscode.cpptools",
+		"plorefice.devicetree",
+		"trond-snekvik.kconfig-lang",
+		"twxs.cmake",
+	],
+	// List of extensions recommended by VS Code that should not be recommended for users of this workspace.
+	"unwantedRecommendations": [
+
+	]
+}